Sewing method and linear punching multi-needle machine therefor



29, 1968' I RoHRLlcK E-rAl. 3,407,764

SEWING METHOD AND LINEAR PUNCHING MULTI-NEEDLE MACHINE THEREFOR Filed uay"2:s, 1966 11 sheets-sheet 1 v 'unumg- SEWING METHOD AND LINEAR PUNCHING MULTiI-NEEDLE MACHINE THEREFDR Filed may 23, 196e M. K. RQHRLICKETAL 11 Sheets-SheenI 2 m. e M mnmu uEH @Ts ...,Awo Kwu ,M V.

Oct. 29, 1968 RHRLICK ETAL 3,407,764.

SEWING METHOD AND"LINEAR PUNVCHING MULTI-NEEDLE MACHINE THEREFOR Filed May 23, 1966 v 11 Sheets-Sheet 3 ll wm/rms:

MK. RoHRLIcK ApLATUYUPPE 85 ELA. sezGmN v; v-Ro u.

'Arian/vir' OCt- 29, 1968 M. K. ROHRLICK ETAL 3,407,764

SEWING METHOD AND LINEAR PUNCHING MULTI-NEEDLE MACHINE THEREFOR Filed May 23, 1966 11 Sheets-Sheet 4 VITI/0K5 i MK. RoHRucK A. LAruLnPPe 1 R\..d. bEGunJ v. RorH Ct- 29, 1968 M. K. ROHRLICKVETAL 3,407,764

SEWING METHOD AND LINEAR FUNCHNG MULTI-NEEDLE MACHIVNE THEREFOR Filed May 25, 1966 11 Sheets-Sheet 5 MK. ROHRLICK A. LATuuPPe P.\ .J.'2 EGON y Arrawfx Oct. 29, MK. RoHRLlcKf-:TAL

SEWING METHOD AND LINEAR PUNCHING MULTI-NEEDLE MACHINE THEREFOR Filed May 23, 1966 11 Sheets-Sheet 6 Ammin mum munir "ugvgmf L l/VVI/Vl95: M-K- ROHRLIQK A. LATULWPE PLA. SEGUIN 04.29, 1968l M. K, RoHRLlCK- sul. 3,407,754

SEWING METHOD AND LINEAR PUNCHING MULTI-NEEDLE MACHINE THEREFOR vFiled ay 23, 196e 11 sheets-Sheet s @i2/0 yl oct. 293 14968 M.K. RoHRLlcK ETAL 3,407,764

`SEWING METHOD AND LINEAR PUNCHING MULTI-NEEDLE MACHINE THEREFOR 11 Sheets-Sheet lo Filed may 23, 1966 KE www Lnu l y mui M A man@ M .WN @Lua U MARv ct 29, 1968 M. K. RoHRLlcK ETAL 3,407,764

SEWING METHOD AND LINEAR PUNCHING MULTI-NEEDLE MACHINE THEREFOR Filed may 23,1966 11 sheets-sheet 11 A. LArumMve R\..J. bEGuuJ V. RQTH lffalM/EY United States Patent O1 iice 3,407,764 Patented Oct. 29, 1968 3,407,764 SEWING METHOD AND LINEAR PUNCHING MULTI-NEEDLE MACHINE THEREFOR Michael K. Rohrlick, Westmount, Quebec, Armond Latulippe, Lachine, Quebec, Paul L. J. Seguin, Pierrefonds, Quebec, and Victor Roth, Dollard des Ormeaux, Quebec, Canada, assignors to Slax Inc., Lachine, Quebec, Canada Filed May 23, 1966, Ser. No. 559,653 21 Claims. (Cl. 112-262) ABSTRACT OF THE DISCLOSURE A method of making a stitch line in which portions of a first thread are drawn through a fabric at spaced aligned points to form loops above the fabric, a second thread is inserted through the loops and the rst thread is pulled to tighten the threads against the fabric.

A machine Ifor making such a stitch line comprising a row of vertical needles movable together through the fabric and having a hook for holding a first thread; a wheel beneath the fabric displaceable along the row of needles and having a protrusion which, at each turn, successively brings the first thread on the hooks of the needles; a series of horizontal forks above the fabric to open up the loops when the needles move above the fabric with the first thread hooked onto the needles; a shuttle to draw a second thread through the opened loops and drawing wheel rotatable in reverse directions and to which the ends of the first thread are connected to pull on the said first thread to tighten it against the fabric after having removed the loops.

The present invention generally relates to the sewing machine art and more specifically to a method and a machine for making a stitch line, that is, a line made up of a succession of sewing stitches. The invention also relates to a stitching needle 4for carrying out the method and for use with the aforesaid machine.

There presently exist multiple needle sewing machines and these are useful for the manufacture of compounded fabrics, that is of fabrics made up of several layers, such as carpets, insulation blankets, quilts, mats or the like thick sheet fabric material. However, these machines are unadapted for the sewing of pieces of wearing apparel along the seam thereof. This work is presently made on conventional sewing machines where the stitches of one line are made one at a time although machines do exist where more than one stitch line is made at a time and this leads to the multiple needle sewing machine mentioned above. However, in both cases it will be noted that the stitches of one line are made one at a time which means that the material has to be continuously moved under the one or several needles. It will be appreciated that this is a lengthy procedure which could be considerably shortened if a complete line of stitching could be made in one single operation of the sewing machine.

It is consequently a main object of the invention tol provide a new sewing machine capable of making a complete line of stitching in one single operation which means that a piece of apparel or other articles made of fabric material could be made in one very rapid operation.

Another object of the invention lies in the provision of a method for making the aforesaid stitch line and finally a further object of the invention resides in the provision of a needle especially adapted for carrying out the abovementioned method as well as for use in the aforesaid machine.

It will be appreciated that with these various objects in mind, the work of connecting two pieces of apparel or other like articles along a seam thereof would be extremely simplified and much more rapid thus providing a substantial saving in the manufacture thereof.

The above-noted objects may be obtained in a method according to the invention for forming a sewing stitch line on a piece of fabric, the said method comprising drawing portions of a first thread through said fabric at spaced aligned points to form thread loops projecting from one surface thereof while portions of the said first thread intermediate said looped portions depend from the other surface; inserting a second thread through said loops; pulling on the said depending thread portions to force said second thread through said fabric to tighten said threads against said fabric.

The machine for making such a sewing stitch generally comprises a series of pointed needles which are movable vertically from a first position above the fabric to a second position where they project through the fabric with the pointed ends thereof located below the fabric, the needles being formed with thread-holding means adjacent the pointed ends thereof; a first thread and means to draw said first thread beneath said fabric; means gripping the rst thread intermediate the ends thereof operable to cause engagement of the first thread with the holding means of the needles when the needles are in the said second position whereby the said needles may move to the first position with a portion of the first thread projecting through the fabric to form loops thereabove; means provided to open the loops to thus form a passage while the first thread portion is held by the needles in the first position; shuttle means and a second thread drawn by the shuttle means through the passage and further means provided for pulling on the ends of the threads to tighten them against the fabric.

It will be appreciated that reference in this specification to a piece of fabric includes a fabric made up of several layers or sheets of the like or different materials, the invention not being limited by the number of thickness of such sheets of fabric.

It is believed that a better understanding of the invention will be afforded by the description that follows of a preferred embodiment having reference to the appended drawings wherein:

FIG. l is a perspective partial view of the machine of the invention;

FIG. 1A (last sheet of drawing) is a plan view of the thread laying mechanism;

FIG. 2 is a partial view in cross-section of the working table of the invention;

FIGS. 3, 6, 7, 8, 9 and 10 are perspective views similar to that of a portion of FIG. 1 and illustrating the machine at various phases of its operation;

FIGS. 4 and 5 are two side elevation views of the thread gripping means shown with the thread-holding means of one needle;

FIG. 11 is a diagrammatic perspective view particularly intended to illustrate the construction and action of the shuttle means;

FIG. llA is an elevation view of the shuttle and of the thread cutting means;

FIG. 12 is a side elevation view illustrating the shuttle as it is driven through the passage formed by the thread loops;

FIG. 13 is a plan view illustrating the shuttle means as it is entering the passage created by the -thread loops;

FIGS. 14 and 15 are two diagrammatic views in perspective illustrating the disengagement of the thread loops from the threading needles;

FIGS. 16 and 17 are two cross-sectional views of the piece of `fabric as the two threads are being interlocked;

FIG. 18 is a cross-sectional view illustrating the first and second threads, when interlocked;

FIG. 19 is a perspective view of the needle used with the method and machine of the invention;

FIGS. 20A to 20F are timing diagrams of the major components of the machine;

FIGS. 21A to 21E are sequential diagrammatic views of the movement of the shuttle means;

FIG. 22 is a perspective view of the top part of the machine, partially broken away to shown certain features;

FIG. 23 is a side elevation view with parts shown in cross-section;

FIG. 24 (first sheet of drawing) is a perspective view of part of the bottom L-shaped operating member;

FIG. 25 is a diagrammatic view of a master cam arrangement for the major components of the machine.

Generally, and with reference to the drawings, the machine of the invention for making a stitch line has a table 6 over which lies a piece of fabric 1, shown as made up of two pieces of cloth 2 and 4 (FIG. 2). The machine comprises a bank of needles 3 mounted on a needle bar 5, by means, hereinafter described, for displacement vertically from a first position above fabric 1 to a second position where the needles project through said fabric with the pointed ends thereof located below fabric 1. The two extreme positions are shown in FIGS. 1 and 6 respectively. The position of the needles must be construed relative to the machine, i.e., the ylatter may be upside down, sideways, etc.

Needles 3 are each formed with a thread-holding means 7 adjacent the pointed end 11 thereof as particularly illustrated in FIG. 19. More specifically, each needle comprises an elongated body 9 formed with a groove 13 starting from the inward edge 15 of pointed end 11, edge 1S defining a thread-receiving shoulder preferably inclined toward pointed end 11 whereby to ensure secure sitting of the thread, in a manner to be hereinafter discussed.

Body 9 -is also formed with a bulge 17 projecting from the bottom of groove 13, bulge 17 being slitted longitudinal-ly of body 9 as at 19 for the reception of a locking arm 21 pivoted, as at 23, to the bulge 17 and of such a length as to rest on the outer tip 25 of thread-receiving shoulder 15, as shown in dotted lines. Thus, locking arm 21 will retain any thread sitting on shoulder 15 when closing recess 27 formed by shoulder 15 and bulge 17.

The pivot connection of locking arm 21 to bulge 17 should preferably be such that arm 21 be frictionally held into any position whenever no force is app-lied thereon. Thus, in FIG. 19, lever arm 21 has been raised and will remain in that position under friction until another force brings it down against tip 25.

Alternatively, the body 9 of the needle and the pivot 23 could be made of rigid non-magnetic material, the arm 21 made of magnetizable material while two magnets 14 and 16 would be provided at the locations shown in FIG- URE 19 whereby to force arm 21 one way or the other depending on its location in relation to pivot 23.

When all the needles are in the second position beneath the table 6, a first thread is brought under the table and hooked on the successive needles which are then moved up through the fabric material to form loops thereabove. A second thread is drawn through the successive loops and a tension is applied to the first thread to cause locking of the two threads against the fabric material.

Referring now back to FIGURE l, a first thread 29 is provided beneath fabric 1 and is brought into position by a thread-laying mechanism illustrated in both FIGURES 1 and 1A.

This mechanism comprises a laying arm 31 which is the rod of the piston (not shown) reciprocable in a cylinder 33, preferably air-operated. Thread 29 is drawn from a bobbin (not shown) through a guiding tube 3S, the bobbin having in known manner a mechanism for resisting unwinding thereof to thus produce a slight tension in the thread 29.

The thread 29 is gripped by a fork 37 provided at the bent end 39 of laying arm 31, bent in the direction of the needles 3. It is intended to lay a portion of thread 29 on and between two tensioning wheels 41 and 43.

Wheel 41 is formed of a bottom disc 45 having a peripheral upstanding nylon skirt 47 provided with a series of narrow slits 49 for the reception of the thread 29. The slit portion of skirt 47 is thin enough to allow flexibility and bending thereof when the bent end 39 passes thereover as will be explained hereinafter.

Wheel 43 also has a bottom disc 51 and a peripheral skirt 53. It is formed with a pair of overlapping ears 55, 55' projecting from the upper border of skirt 43. The latter lies at a lower level than the `arm 31 and the fork 37 and therefore need not be flexible.

The distance between the overlapping ears 55, 55 and the branches of the fork 37 is gradual to allow easy insertion of the thread 29 and is narrow enough at the bottom to safely retain the said thread 29.

From FIGURE 1A, it will be noted that fork 37 is pivotally mounted at the extremity o-f bent end 39 but is spring-pressed clockwise in alignment with the bent end where it is brought to a stop by abutment.

The thread-laying mechanism operates as follows:

At the beginning of the sewing operation, the laying arm 31 is retracted in the cylinder 33 with the bent end 39 and the fork 37 located at the right of FIGURES 1 and 1A. The end of the thread 29 is first brought in engagement in the fork 37 by hand. At the appropriate time to be determined later, the arm 31 is extracted from the cylinder 33, the fork 37 bends the slitted top of wheel 41 as it passes thereover and as it moves away therefrom the thread 29 is pressed into engagement in two opposite slots 49 as shown in FIGURES 1 and lA. The arm 31 and fork 37 continue to move leftward until the end of the piston stroke is reached. The situation is then that of FIGURES l and 1A.

It will be rememberedthat the top border or edge of the skirt 53 of wheel 43 is at a lower level than fork 37 and is therefore unaffected by its movement thereover. However, ears 55, 55 project beyond the level of the lfork 37 but are out of the way during the fork-laying operation.

The wheel 43 is mounted on a shaft 57 and is then rotated clockwise to force ears 55, 55 to grip the thread 29, the latter being then drawn from the bobbin and slightly tautened by Winding it partially Iaround the drum formed by the outer surface of the skirt 53. A pressure roller 59 is spring-pressed against the said outer surface to ensure a firm grip of the thread thereagainst. When this is attained, the thread 29 is cut by means of a reciprocating electric-al hot wire 61. The arm 31 is then retracted into the cylinder 33.

It will be appreciated that as the fork 37 moves over the wheel 41, it is pivoted counterclockwise against a spring bias (not shown), in the manner illustrated in dotted lines at the right of FIGURE 1A.

As the 'fork 37 reaches past wheel 41, it is straightened by the spring bias and the thread 29 is forced between the two prongs o-f the fork due to the inclination of the thread between the wheel 41 and the guiding tube 35. The threadlaying mechanism now stands by for the next cycle of operations.

After a cycle is completed, that is when the two threads have been locked into the fabric material, the thread 29 is cut by energizing the electrical hot cutters or wires 60 and 62 between the wheels 41 and 43.

The thread 29 is now laid out for the remaining steps of the method.

Successive portions of first thread 29 are thereafter brought into engagement with the thread-receiving shoulders 15 of the needles 3 (FIG. 19), by a hooking and releasing means comprising a rotatable member 63 beneath fabric 1, rotatable member 63 being displaceable along the needles of the bank and having a peripheral protrusion hooking the said successive thread portions and bringing them adjacent the thread-holding means 7 of the successive needles 3 when the latter are in the second position, that is beneath fabric 1. The hooking and releasing means also includes a thread-releasing member 65 disposed in the path of said protrusion and adjacent the j thread-holding means 7 during rotation and displacement of the rotatable member to cause release of the first thread 29 from the said protrusion and engagement thereof with the thread-holding means 7. Thus the needles may subsequently move Ifrom the second to the first position with the said portions of first thread 29 projecting through fabric 1 to form successive loops thereabove.

More specifically, rotatable member 63 comprises a pair of spaced parallel cams 67 connected to one another in any known manner, each cam being formed with a projecting finger 69 forming the said protrusion and the thread-releasing member 65 is a solid element having a downwardly sloping face 70 projecting in the space ben tween the two cams 67 and directed toward the needles 3 whenever the latter are in the said second position below fabric 1.

Rotatable member 63 formed of the two cams 67 is slidably mounted on a driven shaft 71 and is held thereon by means of a key 73 fitted into a suitable keyway 75, the key 73 extending through a slot 77 Yacross the bore of member 63 in such a manner that the latter is. brought into rotation by shaft 71 but can be displaced longitudinally therealong by sliding thereover.

Thread-releasing member 65 is secured to a block 79 acting as a nut screwed on a threaded shaft 81. The latter is brought into rotation by any known reversible drive such as by being connected to a reversible DC motor 62 through a magnetic clutch and brake unit 64. Reversal of the rotation of driving shaft 81 and consequently of driven shaft 71 is controlled by means of two limit switches 231, 233 in the manner hereinafter described.

The block 79 is formed with a pair of spaced cheeks 83 loosely straddling shaft 71 on each side of the rotatable and axially displaceable set of cams 67 of member 63. It will thus be understood that rotation of shaft 71 causes axial displacement of block 79, the latter forcing displacement of rotatable member 63 along shaft 71. More specifically each revolution of shaft 71 brings the cams in successive engagement of a needle.

The thread 29 may be guided by means of a stationary hook 85 on either side of the bank of needles 3 (one only being shown). It is also guided by means of a mov able bank of threading hooks 87 so spaced and disposed in relation to cams 67 as to avoid the latter during rotation and axial displacement thereof. However, the spacing and location of hooks 87 are such as to allow projecting fingers 69 to travel between the successive pairs as they rotate and are moved axially of shaft 71.

The bank of threading hooks 87 are mounted on a hook bar 89 similar to needle bar 5. More specific details of the operation and operating mechanism of hooks 87 will be given further on.

Reference will now be made to FIGS. 11, 11A, 12 and 13 for a general description of the shuttle means.

The latter generally comprises a shuttle assembly 91 intended to draw a locking thread or second thread 93 through a series of aligned V-shaped loops defined by portions of first thread 29 as explained hereinafter. The

loops are disposed between two open ends of an otherwise endless shuttle guide 95.

More specifically, the shuttle assembly comprises a relatively heavy thread-pulling body or shuttle 97 having a forward pointed end and a general shape in cross-section to fit in the lower triangular portion of the above-mentioned first thread loops. However, it may be shaped as at 97 to travel through the upper portion of the loops. Shuttle 97 is driven through the passage formed by the succession of the aforesaid loops by means of a pusher arm 99 having a driving lug 101 projecting in the direction of shuttle 97 to abut the rear part thereof. The other end of pusher arm 99 is fixed to an endless link chain or belt 103 winding around two end sprockets or wheels 105. It should be noted that there is no positive connection between the pusher arm 99 or its driving lug 101 and the shuttle 97 so that the inclined lower strands 29" (see FIG. 15) of the loops will pass freely between the shuttle 97 and the pusher arm 99 during displacement of the said shuttle through the loop passage.

Shuttle 97 has a conventional thread pick-up lever 107 for holding second or locking thread 93 to pull it through the loop passage. Reference will again be made to lever 107 when describing FIGS. 21A to 21E.

Shuttle guide has an inverted Lshape in cross-section with a downward flange 109 and an upward inclined fiange 111 suitable to loosely accommodate shuttle 97. It will be understood that lug 101 of pusher arm 99 enters into the shuttle guide 95 whereby' to drive shuttle 97 all around the said guide.

A pair of openings 113 are cut through the web of the L-shaped guide 95 at the two arcuate ends thereof.

The sewing stitch of the invention is illustrated in its completed form in FIG. 18 and will be seen to comprise the aforesaid first thread 29 having portions thereof extending through the fabric 1 at spaced aligned points and from one face thereof, and of the `aforesaid second or locking thread 93 having portions thereof also extending through the fabric at the said spaced points but from the other face of fabric 1, the latter second thread portions interlocking with the first thread portions at the said points. As will be noted, the two thread portions generally meet at mid-point through fabric 1.

The general description of the operation of the machine and the various steps of the method will now be given with particular reference to FIGS. 1 through 17 and 20 while further features of the invention will be added.

At the end of one cycle of operations, block 79 is brought back to the starting point (left in FIG. l) by driven shaft 71 and driving shaft 81 through the reversible drive. Further details of the working of the reversible drive will be given hereinbelow.

Thereafter, needles 3 are driven through fabric 1 from the first position of FIG. 1 to the second position of FIG. 3, causing locking arms 21 to pivot upwardly. (This is the portion ab in the graph of FIG. 20A.l

The position of threading hooks 87 is such, as aforesaid, that each needle 3 stands forwardly of and between one pair thereof.

As block 79 moves cams 67 forward, fingers 69 thread each pair of hooks 87 successively; FIG. l showing the said fingers aboutto pass between the first pair of hooks.

In FIG. 3, fingers 69 have caught a portion of thread 29 and have brought it in rotation toward the pointed end of the first needle 3. One end of thread 29 is retained by wheel 43 on the machine while the other end is being drawn from the supply bobbin equipped with the aforesaid resisting machanism so as to maintain thread 29 in taut condition.

In FIG. 3, fingers 69 have been rotated to a point where the thread portion is immediately adjacent the first needle and is ready to abut the downwardly inclined arcuate sloping face 70 of the thread-releasing member 65. Further rotation of fingers 69 will cause rising along sloping face 70 of the thread portion spanning-the space between the said two fingers to a point where the said thread portion is about to fall on the thread-receiving shoulder 15 (FIG. 19) and into the recess 27 of the first needle. This is the situation in FIG. 4. Thereafter, thread 29 is freed from fingers 69 and is positively engaged on the first needle. This is the situation in FIG. 5 as well as in FIG. 6.

Shaft 81 keeps on rotating, causing rotation of driven shaft 71 and further advancement of block 79 with the cheeks 83 thereof shifting rotatable member 63 further toward the second'needle of the bank.

As shown in FIG. 7, the situation particular to FIG. 3 is repeated in relation to the second needle. In FIG. 8. it is assumed that al1 of the needles have been stringed with thread 29, taut between the threading hooks 87 and the said needles.

The next sequence is shown in FIG. 9 where the needle bar is raised, by means hereinafter described, to cause the needles 3 to move from the second to the first position of the fabric 1. It will be understood here that any tendency of thread 29 to free itself from the needles 3 during withdrawal thereof from the fabric has been prevented by the closing of recesses 27 (FIG. 19) by the falling of locking arms 21 positively forced to pivot counterclockwise. Positive movement of arms 21 is described furtheron.

During that process, the threading hooks 87 have moved upwardly with pivoting of hook bar 89 keeping the thread taut between threading hooks 87 and the needles 3.

In moving above fabric 1, the thread portions between each pair of threading hooks 87 have formed a series of loops 29.

After the needles 3 have moved fully to the first position above fabric 1, a bank of loop-opening forks 115, fixed to a fork bar 117, comes into action by moving substantially at right angles to the needles 3 to spread the two strands of loops 29 apart and force them into a general triangular configuration, illustrated in FIG. 10.

Thus, the succession of triangular-shaped loops 29', of like configuration in cross-section, define a shuttle passage.

We now come to the shuttle means previously described in connection with FIGS. 11, 12 and 13.

After the portions of thread 29 have formed the triangular loops 29', endless chain or belt 103 is made to drive shuttle 91 from -one open end of shuttle guide 95 toward the other open end thereof. The speed of shuttle 91 ought to be sufliciently great to prevent wobbling thereof and possible entanglement with the aforesaid loop strands 29". Movement of shuttle 91 and pusher arm 99 through the successive loops 29' is as described above.

We now come to the final steps of the method and these are illustrated in FIGS. 14 to 17.

The loop-opening forks 115 are made to withdraw and subsequently a thread disengaging bar 119 is brought laterally against loops 29 to free them from the needles 3 while the fiexible teeth 121 of a tension distributing comb 123 are inserted in loops 29 as close as possible to the surface `of the material being sewn, above the second thread 93. Immediately thereafter hook bar 89 is pivoted downward to gradually destroy loops 29 and the situation becomes that of FIG. 16 where the loops have reached the level of the locking thread 93. The flexible teeth 125 of a second tension distributing comb 127 are inserted between the loops beneath the table 6, the hooks 87 release the said loops and tension is applied to the thread 29 by reverse rotation of the tensioning wheels 41, 43 (FIGURES 1 and 1A), the thread winding around the skirts of the said wheels, being retained thereon by the friction rollers 59, 59. The teeth 121 and 125 prevent untimely locking of the loops in the material.

When the bottom loops have all reached the bottom of the table 6i, the teeth 125 are withdrawn, a further tension brings the loops completely against the material, the upper teeth 121 are then withdrawn and a still further tension locks the two threads 29 and 93 in the material as shown in FIGURE 18.

Rsum of the various operations of the major `components will now be given with reference to the graphical illustration thereof shown in FIGS. 20A to F.

As shown in FIG. 20A, the bank `of needles 5 is first moved down to the second position from points a to b and remains in that position until all needles are threaded and point c is reached. Between c and d, there is a slight dip to permit closure of locking arms 21 as hereinafter explained and the needles are then brought up above fabric 1 to point e. There is then a slight dip between points f and g to allow for the opening of loops 29' by forks 115, followed by a rise after release ofi the loops from the needles by the disengaging bar 95.

Portions of bottom thread 29 are hooked on the needles 3 by the threading cam 63 during the time the latter are in lowered position between points b and c of FIG. 20A. Movements of the bottom thread and threading cam are illustrated in FIGS. 20B and 20C, respectively.

As mentioned above, forks are brought into action between points f and g of the needles 3 (see FIGS. 20A and 20D).

Shuttle 91 is drawn through loops 29 when the forks 115 are in operative position so that FIG. 20E shows a corresponding movement of the shuttle, the latter returning to starting position during the remaining of the cycle.

Upward pivoting of tautening hooks 87 takes place when the needles 5 are moved upwardly into rst position as shown in FIG. 20F. They will stay upward until point g of the graph of FIG. 20A at which time the thread, after release from the needles, is pulled back through fabric 1 as shown in FIG. 16. At that time, the loops are removed from engagement with hooks 87.

Now for further preferred construction features of the machine of the invention.

FIGS. 21A to 21E illustrate the movements of the shuttle 91 during one cycle. The path of the shuttle 91 is shown as a dash and dot outline which follows the shuttle guide 95 with the `addition of inwardly directed actuating shoulders 129 (see also FIG. l1) intended to force pivoting of the thread pick-up lever 107.

As shown in FIG. 13, pick-up lever 107 is an arcuate member pivoted at 131 to shuttle 97 and driven clockwise by a return spring 133 to force the forward part thereof in engagement with the shuttle. With the two actuating shoulders 129, it will be understood that when shuttle 91 reaches the starting point at the rightward end of shuttle guide 95, the corresponding actuating shoulder 129 forces pivoting of lever 107 counter-clockwise to disengage the forward end thereof from the shuttle body. Upon further movement of shuttle 91, the end of thread 93 that hangs from support 135 becomes inserted between the shuttle body and the front end of lever 107. At that moment, the rear end thereof leaves the actuating shoulder 129 and under the action of spring 133 the front end is forced against the shuttle body clamping the end of thread 93 in a manner clearly shown in FIGS. 11A and 13.

In the succeeding FIGS. 21B and C, shuttle 91 is driven through the succession of loops 29 forming the aforesaid passage to finally reach the second actuating shoulder 129 which, by forcing counter-clockwise movement of lever 107 releases thread 93. It is to be understood that in one cycle, shuttle 91 leaves the position of FIG. 21A at time f (FIG. 20E) goes around the shuttle guide to the starting point, stops and awaits the next time f of the following cycle.

After thread 93 has extended through the loop passage and has been released from shuttle 91, a hot wire 137 becomes energized to cut it. The relative mounting of thread support 135 and cutting bridge or hot wire 137 is clearly shown in FIG. 11A.

Starting and stopping of chain 103 and sprockets 105 will be explained hereinafter in relation to the cam arrangement of FIG. 25.

It is to be understood that the shuttle means could be replaced by a system similar to the laying of thread 29, as described above in reference to FIGS. l and 1A.

Referring now particularly to FIGURES 22 and 23, it will be seen that the needle bar 5 is fixedly mounted centrally of two transverse supports 138, the outer ends of which are secured at the upper ends of rods 139 extending across the table 6 and guided in cylinders or sleeves 141 beneath and fixed to the said table and that many also act as supports therefor. The center of bar 5 is fixed at the end of a piston rod 143 (FIGURE 23) of an airoperated cylinder 145 also having an operating rod 147 connected to the cylinder piston 4and actuating limit switches 149, 149. The operating cylinder 145 and the limit switches 149, 149' are parts of a sequence control 9 unit 151 (FIGURE 25) to be referred to again hereinafter.

The cylinder 145 may be supported by a pair of transverse beams 153 that may be parts of the general frame of the machine illustrated by side members 155 and columns 157.

As mentioned previously, the threading hooks 87 are fixed to a hook bar 89 which is part of a hook mechanism best illustrated in FIGURES 1, 1A and 23. This mechanism is made up of an upper rigid frame comprising the said hook bar 89, a rear bar 159 and two side bars 161 interconnecting the bars 89 and 159. This upper frame is connected in turn to a lower frame 163, fixed in relation to the machine, through a pair of :connecting links 165, 166 of uneven lengths at each end of the upper and lower frames; the links being pivotally connected, at their ends to both frames, respectively. The hook mechanism is actuated by an air cylinder 167 pivotally connected at one end to the frame of the machine (or table support) and to the upper frame of the mechanism.

With the above mechanism, it is possible to impart a somewhat sinuous upward movement to the hooks 87 starting from the horizontal position shown in full lines in FIGURE 23 to the upwardly inclined position shown in dotted lines at 87. The lengths of the links 165, 166 should be such as to move the hooks 87 to the dotted position while avoiding upward movement of the bent end of the hooks to prevent the thread 29 from slipping away therefrom.

Retraction of the hooks and disengagement from the thread 29 is also obtained by movement of the air cylinder 167 after the loops 29 have been collapsed (FIG. 16).

The tension combs 123 and 127, respectively bearing the teeth 121, 125, are operated from air cylinders 169, 171. If only one central air cylinder is used, the combs 123 and 127 should be properly guided to ensure straight reciprocating motion.

Movement of the loop forks 115 and fork bar 117 is obtained and guided in a similar manner by at least one air cylinder 173.

A pressure foot plate 175 having a central longitudinal slot 177 is provided to press the fabric 1 against the table. The pressure is applied by means of four air cylinders 179 (FIGURES `22 and 23) mounted on the frame of the machine such as on transverse members (not shown) extending from the side members 153. Since the foot plate 175 is applied at the beginning of one cycle of operation and lifted at the end of the cycle comb 123, loop forks 115 and their operating air cylinders 169, 173 may advantageously be mounted thereon.

Referring now to FIGURES 2 and 24 (first sheet of drawing), there are shown mounted beneath pressure foot plate 175 and over table 6, L-shaped operating members for opening and closing arms 21 of the needles 3 during their downward and upward displacements, respectively, across slot 179 of the pressure foot 175 and 181 of table 6, the latter serving for the passage of the needles 3 through the table 6, as will be understood.

The upper needle arm operating member has a horizontal part 183 secured beneath the pressure foot 175 and a vertical part 185 extending upwardly through the slot 179. The needle arm operating member for the table 6 has a horizontal part 187 fixed on the table and a vertical part extending downwardly through the slot 181.

When the needles are moved down, as seen in FIG- URE 2, locking arms 21 are forced upward by part 185. The needles then move further until the arms 21 reach the lower tip of part 189 and remain in that position during engagement of the thread 29 on the needles 3. Thereafter, needles 3 move down further, as explained above in reference to the dip c, d of FIGURE A, until the position shown in dotted lines in FIGURE 2 is reached. Any upward movement of the needles 3 will then causing closing of the locking arms 21.

To ensure proper operation of the above device, the upward and downwardly extending parts185, 189 may be moved slightly in the path of the locking arms 21 to force the needles rightward a short distance when sliding on the said parts and then leftward when released therefrom to obtain the positions of FIGURE 2.

The downward part 189 of the table L-shaped operating member is apertured to allow passage of the teeth of the comb 127. The apertures 188 (FIGURE 24) are elongated whereby to allow vertical flexibility to the teeth- 125 while restraining the lateral displacement thereof.

The disengaging bar 119 mentioned in relation to the description to FIGURES 14 to 17 is actuated by a pair of levers 191 each pivoted intermediate the ends thereof to a bracket 193 secured to the needle bar 5. An air cylinder 195 rocks the said lever to cause disengagement of the loops 29 from the needles 3, in the manner aforesaid (see FIG. 22).

The coordination and synchronization of the various movements of the above-described parts may be obtained by an electronic computer, timer and programmer but for the purpose of completing the description of the machine o f the invention, a specific arrangement will now be described in relation to FIGURE 25.

In the latter figure, a motor assembly 197 is shown that is adapted to rotate a cam shaft 1.99 through one revolution per cycle. Upon cam shaft 199 are secured' for rotation therewith a series of cams such as cams 201 to 217 adapted to energize the various circuits of the component parts of the machine such as circuits a to j. The positions shown are those immediately prior to the beginning of a new cycle.

When the motor assembly is energized for one cycle, manually or otherwise, the first component coming into action is the pressure foot 175. As said above, the latter moves down against the fabric material 1 and remains under pressure till near the end of the cycle, a lapse of time being thereafter allowed to permit sliding of the material which is fed from adjacent rolls in a continuous manner. Preferably, the motor assembly 199 should be energized automatically by a photo-electric cell arrangement at the start of each cycle.

The movements of the pressure foot may be obtained by means of conventional single--acting upwardly biassed air cylinders 179, the actuation of which is regulated by an air control valve of known type such as those manufactured by the firm Verso Products Inc., Englewood, NJ., and known as manifold mount valves.

When the electrical circuit a of the air control valve is energized, as when a exible contact arm 221 is forced to move out of the depression 225 of the cam 201 to contact a stud 223 to close the circuit a, the cylinders 179 are pressurized to bring the pressure foot 175 down against the fabric material. When the circuit is deenergized, as when arm 221 is allowed to fall in the depression 225, the pressure foot 175 moves up under the bias of the cylinders and air is exhausted therefrom.

The same principle applied for the other simple reciprocating motion parts such as the thread-laying arm 31 of the circuit c, the thread cutters 60, 61 and 62, the loop forks 115 and the upper and lower tension com'bs 123, 127.

As to cutting Ibridge 137 (FIG. 11A), the cutting wire thereof may be heated to cut second thread 93 by closing the corresponding circuit at the appropriate time lby means of a cam arrangement such as those already described.

The tensioning wheel 43 and the chain sprocket wheels 105 are respectively operated 'by motors 226, 229 when energized by their respective cams 207, 215 closing circuits d and z'.

It will 'be noted that the wheel 43 is made to rotate twice per cycle as mentioned above. The tension wheel 41, on the other hand, only moves once per cycle and the corresponding cam thereof would therefore have only one bulge (or depression).

At the 'beginning of a cycle of operation, the motor 62 of the reversible drive is idle. Circuit f is energized 'by the bulge on the cam 210 when the thread 29 is finally laid between the two wheels 41 and 43. The reversible drive has a control unit containing a timer assembly including an actuator that starts rotating upon energization of the circuit f. This actuator actuates the DC motor 62 to bring the driving shaft 81 into rotation. When the cam member 63 reaches the end of its stroke, it trips off the limit switch 233 (FIGURE 1) which deenergizes the motor 62 and changes the polarity thereof. The timer actuator keeps moving until the threading hooks 87 are retracted. At that time, it operates the motor 62 again, :but in reverse, which brings the cam member 63 back to its starting position where the limit switch 231 cuts it off.

Movements of needles 3 are obtained by means of a double-acting air cylinder 145 controlled by a sequence control unit as shown in circuit b which comprises a multiple `way solenoid-operated valve for control of the admission and exhaust of air in the cylinder 145. This valve is, in turn, operated by a pair of relays, one affecting the up motion of the cylinder 145, the other the down motion thereof. The two double-throw micro switches 149, 149' (FIGURES 22 and 23) energize the up and down relays when depressed by the rolled flange 235 and collar 237 at the end of the -operating rod 147 of the cylinder 145. Finally, lan adjustable timer is provided in the unit to give the deferred motions mentioned previously and corresponding to dips c, d and f, g of FIGURE 20A.

A relay circuit such as described briefly above, relates to a well known technique and need not 'be detailed any further.

The actuation of air cylinder 167 and threading hooks 87 (circuit g) could be obtained with a similar sequence control unit and by means of an air cylinder of the double-rod construction type such as cylinder 145.

For the design of pneumatic circuit, reference may be had to the publication called Maxam Pneumatic Circuit Design published by the Maxam Power Limited of Camborne, England.

An important feature to be noted, in the above described machine, it the thread reserve which is unlimited, as compared to the very llimited reserve available in other types of sewing machines.

Although a specific embodiment of the invention has just been described, it will be understood that various modifications may Ibe made thereto without departing from the spirit of the invention the scope of which is set forth in the appended claims.

We claim:

1. A method of making a stitch line through a piece of fabric, comprising:

(a) drawing portions of a first thread through said fabric at spaced aligned points thereon to form thread loops projecting from one surface thereof while portions of said first thread intermediate said looped portions depend from the other surface;

(b) inserting a second thread through said loops, and

(c) pulling on said first thread to tighten said threads against said fabric.

2. A method of making a stitch line through a piece of fabric, comprising:

(a) drawing successive portions of a first thread simultaneously through said fabric at spaced aligned points thereon to form thread loops projecting from one surface thereof and allowing portions of said first thread intermediate said looped portions to depend from the other surface;

(-b) inserting a second thread through said loops;

(c) pulling on said depending thread portions to bring said loops -against said second thread, and

(d) pulling on the ends of said first thread to tighten said threads against said fabric.

3. A method of making a stitch line through a piece of fa'bric, comprising:

(a) drawing successive portions of a first thread simul taneously through said fabric at spaced aligned points thereon to form thread loops projecting from one surface thereof and allowing portions of said first thread intermediate said looped portions to depend from the other surface;

` ('b) inserting a second thread .through said loops;

(c) pulling on said depending thread portions to cause collapse of said loops on said second thread and Iformation of further loops projecting from said other surface;

(d) pulling on said first thread to cause collapse of said further loops;

(e) further pulling on said first thread to tighten both said threads against said fa'bric.

4. A machine for making a sewing stitch through a piece of fabric comprising:

(a) a series of pointed needles each formed with thread-holding means adjacent the pointed end thereof;

(b) means to move said needles simultaneously vertically to and from a first position on one side of said fabric and a second position where said needles project through said fabric with the pointed ends thereof located on the other side of said fabric;

(c) a first horizontal thread on said other side of said fabric;

(d) means to grip said first thread intermediate the ends thereof and operable to cause engagement of the said first thread with said holding means when said needles are in said second position whereby said needles may move to said first position with portions of said first thread projecting through said fabric to form loops on said one side;

(e) means opening said loops to define a passage while said first thread portions are held lby said needles in said first position;

(f) shuttle means and a second thread to be drawn by said shuttle means through said passage, and

(g) means pulling on the ends of said first thread to tighten said threads against said fabric.

5. A machine for making a sewing stitch through a piece of fabric, comprising:

(a) aligned pointed needles each formed with threadholding means adjacent the pointed end thereof; (b) means to move said needles simultaneously vertically to and from a first position above said fabric and a second position where said needles project through said fabric with the pointed ends thereof located below said fabric;

(c) a first horizontal thread below said fabric;

(d) a rotatable member displaceable along said needles l .and having a peripheral protrusion to successively hook portions of said first thread during rotation and displacement thereof and to successively bring the said portions adjacent said needles when the latter are in the said second position;

(e) a thread-releasing member disposed in the path of said protrusion and adjacent said thread-holding means to cause release of said first thread from said protrusion and engagement thereof with said thread-holding means, whereby said needles may move from said second to said first position with said portions of said first thread projecting through said fabric to form loops thereabove;

(f) means opening said loops to define a passage while said first thread portion is held by said needles in said first position;

(g) shuttle means and a second thread to be drawn by said shuttle means through said passage, and

(h) means pulling on the ends of said first thread to tighten said threads against said fabric.

6. A machine as claimed in claim 5, wherein each needle thread-holding means comprises a lateral recess at the needle pointed end defining a thread-receiving shoulder, a locking arm pivoted to said needle away from said pointed end defining a thread-receiving shoulder, and a locking arm `pivoted to said needle away from said pointed end and recess; said locking arm to close said recess to prevent disengagement of said first thread therefrom and to allow said needles to move from said second to said first position through said fabric.

7. A machine as claimed in claim 6, wherein said needle is made of non-magnetic material and said locking arm is made of magnetizable material, and a pair of magnets on said needle located to bias said arm toward open or closed position depending on its location in relation to the pivot of said arm.

8. A machine as claimed in claim 5, wherein said rotatable member comprises a pair of spaced parallel discs connected to one another; each disc formed with a projecting finger defining said peripheral protrusion Whereby said first thread portions are hooked by said fingers during rotation of said discs with a length of said portions spanning the space between said discs; said discs being disposed so that the pointed ends of said needles successively lie therebetween during displacement of said rtatable member.

9. A machine as claimed in claim 8, wherein said thread-releasing member is a rigid element having a downward surface projecting in said space between said discs and toward said needles whereby to be engaged by said thread portion between said fingers to release the said thread portions from said fingers and to direct said thread portions on said needle thread-holding means.

10. A machine for making a stitch line through a piece of fabric comprising:

(a) a bank of aligned spaced pointed needles each formed with thread-holding means adjacent the pointed end thereof;

(b) means to move said bank of needles simultaneously vertically to and from a first position above said fabric and a second position Where said needles project through said fabric with the pointed ends thereof located below said fabric;

(c) a first horizontal thread below said fabric;

(d) means to grip said first thread intermediate the ends thereof and operable to release said first thread and cause engagement thereof with said holding `means when said needles are in said second position whereby said needles may move to said rst position with portions of said first thread projecting through said fabric to form aligned loops thereabove;

(e) means opening said aligned loops to define a passage while said first thread portions are held by said thread-holding means of said needles when the latter are in said first position;

(f) shuttle means and a second thread to be drawn by said shuttle means through said passage, and

(g) means pulling on the ends of said first thread to force collapse of said loops and tighten said threads against said fabric.

11. A machine for making a stitch line through a piece of fabric, comprising:

(a) a bank of aligned spaced pointed needles each formed with thread-holding means adjacent the pointed end thereof;

(b) means to move said bank of needles simultaneously vertically to and from .a first position above said fabric and a second position where said needles project through said fabric with the pointed ends thereof located below said fabric;

(c) a first horizontal thread below said fabric;

(d) a rotatable member beneath said fabric displaceable along the needles of said bank; said member having a peripheral protrusion to hook successive portions of said first thread and to bring said portions adjacent the thread-holding means of the successive needles when the latter are in said second position;

(e) a thread-releasing member disposed in the path of said protrusion and adjacent said thread-holding means during rotation and displacement of said rotatable member to cause release of said first thread from said protrusion and engagement thereof with said thread-holding means, whereby said needles may move from said second to said first position with said portions of said first thread projecting through said fabric to form successive loops thereabove;

(f) means opening said loops to create a passage while said first thread portions are held by said needles in said first position;

(rg) shuttle means and a second thread to be drawn by said shuttle means through said passage;

(h) means to disengage said thread portions from said thread-holding means and said loop opening means, and

(i) means pulling on the ends of said first thread to tighten said threads against said fabric.

12. A machine as claimed in claim 1.1, wherein said thread-holding means of each needle comprises a lateral recess at the needle point end, defining a thread-receiving shoulder, a locking arm pivoted to the needle away from said pointed end and recess; said locking arm closing said recess to prevent disengagement of said first thread therefrom when the needle moves from said second to said first position through said fabric.

13. A machine as claimed in claim 1.2, wherein said needle is made of non-magnetic material and said locki ing arm is made of -magnetizable material, and a pair of magnets on said needle located to bias said arm toward open or closed position depending on its location in relatio-n to the pivot of said arm.

14. A machine as claimed in claim 11, including a rotatable shaft; said rotatable member mounted thereon for rotation therewith and axial displacement therealong, and means synchronized with said rotatable shaft and operative to displace said rotatable member along said shaft.

15. A machine as claimed in claim 1l4, wherein said synchronized means comprises a rotatable screw threaded driving member; transmission means connecting said screw threaded member to said shaft to cause rotation thereof and a block in mesh with said screw threaded member, said block having a pair of forked arms loosely straddling said shaft on each side of said rotatable and axially displaceable member whereby rotation of said shaft causes axial displacement of said block and of said rotatable member.

16. A machine as claimed in claim 15, wherein said rotatable member comprises a pair of spaced parallel discs connected to one another; each disc formed with a projecting finger defining said peripheral protrusion whereby said first thread portions are hooked. by said fingers during rotation of said dises with a length of said first thread portions spanning the space between said discs; said discs being disposed so that the pointed ends of said needles successively lie therebetween when said needles are in said second position.

17. A machine as claimed in claim 16, wherein said thread-releasing member is a rigid element fixed to said block and having a downward surface projecting in said space between said discs and successively facing each needle of said bank as said block is displaced lengthwise of said shaft whereby said rigid element. is engaged successively by said thread portions between said fingers t0 release the said thread portions yfrom said fingers and direct said portions on said needle thread-holding means.

18. A machine as claimed in claim 11, including means to lay out said first thread below said fabric, said means comprising:

a pneumatic cylinder having a piston rod movable in and out of said cylinder lengthwise of said bank of needles forwardly of said rotatable member;

said rod having an outer end bent in the direction of said needles and provided with a thread gripping fork;

a pair of horizontal spaced discs each mounted for rotation on one side of said bank of needles forwardly thereof;

an upstanding slitted flexible skirt on said disc close 15 to said cylinder to loosely grip said first thread across two opposed slits thereof and a thread gripping fork projecting from the disc away from said cylinder; means pivotally mounting said bent end fork on said :bent end including a resilient bias operable to allow said bent end fork to pivot counterclockwise when hitting said slitted skirt as said rod is retracted in said cylinder, and

thread guiding means along said cylinder forcing said first thread to an angular bend between said slitted skirt and said guiding means whereby to force said bend of -said thread in engagement in said bent-end I fork as said rod retracts into said cylinder.

19. A machine as claimed in claim 18, wherein said means pulling on the ends of said first thread is formed by said rotatable discs, slitted skirt and disc fork.

20. A machine as claimed in Claim 11, wherein said shuttle means comprises:

an endless movable belt;

a shuttle member mounted on Said belt, and

a guiding track for said shuttle open between said bank of needles to allow passage of said shuttle member through said loop passage.

21. A stitching needle comprising:

(a) a body having a pointed end;

(b) said body formed with a lateral recess on the pointed end dening a thread-receiving shoulder, (c) a locking arm pivoted to said body away from said pointed end and recess and adapted to close said recess when pivoted toward said pointed end, and wherein said needle is made of non-magnetic material, said locking arm is made of magnetizable material and there is provided on said needle a pair of magnets located to bias said arm toward or away from the closed position depending on the location thereof in relation to said arm.

References Cited UNITED STATES PATENTS 6,025 l/l849 Hibbert 66-121 1,714,928 5/1929 Sigoda 112-223 XR 2,541,367 2/1951 Kitcat. 3,236,068 2/1966 McDonough 66-111 3,327,498 6/1967 Matthews 66-121 JORDAN FRANKLIN, Primary Examiner.

J. R. BOLER, Assistant Examiner'. 

